Jesus promised the apostles that after He was crucified and ascended into heaven (John 14:2-3), He would send a Helper to them (John 14:15-16). Jesus reminded the apostles after He was resurrected that the Holy Spirit would come and they would be witnesses to Him (Acts 1:1-8).
On the day of Pentecost, this promise was fulfilled when they were immersed with the Holy Spirit at the temple in Jerusalem (Acts 2:1-4). After Peter preached a sermon convicting his Jewish audience of murdering the Messiah who had been promised to them, many in the audience were sorrowful and asked what they needed to do (Acts 2:37). Peter told them to “Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins…”
On that day, 3,000 people obeyed the command and were baptized for the remission of their sins (Acts 2:41). The Lord added these saved individuals to the church (Acts 2:47). This was when the church began and it continued to grow throughout the New Testament as the gospel was spread. The church continues to grow today as people are baptized for the remission of their sins and the Lord adds us to it. The Westwood Village church of Christ is made up of folks who have obeyed this command and are part of the church which Christ built (Matthew
16:18).